exif_orientation.module in EXIF Orientation 7

Module file for EXIF Orientation

File

exif_orientation.module

<?php

/**
 * @file
 * Module file for EXIF Orientation
 */

/**
 * Implements hook_form_alter().
 * Replace the user_validate_picture validator with our own.
 */
function exif_orientation_form_user_profile_form_alter(&$form, &$form_state, $form_id) {
  $key = array_search('user_validate_picture', $form['#validate']);
  $form['#validate'][$key] = '_exif_orientation_validate_user_picture';
}

/**
 * Validates an image uploaded by a user.
 * This is an exact copy of user_validate_picture() except our validator which is added
 * before file_validate_image_resolution(). file_validate_image_resolution resizes the image
 * if it's too large loosing the exif data in the process. The standard validators of
 * hook_file_validate() are run after user_validate_picture() so it cannot be used because
 * the image does not contain the exif data anymore. The only solution is to completely replace
 * the validator from core.
 *
 * @see user_validate_picture()
 */
function _exif_orientation_validate_user_picture(&$form, &$form_state) {

  // If required, validate the uploaded picture.
  $validators = array(
    'file_validate_is_image' => array(),
    '_exif_orientation_validate_image_callback' => array(),
    'file_validate_image_resolution' => array(
      variable_get('user_picture_dimensions', '85x85'),
    ),
    'file_validate_size' => array(
      variable_get('user_picture_file_size', '30') * 1024,
    ),
  );

  // Save the file as a temporary file.
  $file = file_save_upload('picture_upload', $validators);
  if ($file === FALSE) {
    form_set_error('picture_upload', t("Failed to upload the picture image; the %directory directory doesn't exist or is not writable.", array(
      '%directory' => variable_get('user_picture_path', 'pictures'),
    )));
  }
  elseif ($file !== NULL) {
    $form_state['values']['picture_upload'] = $file;
  }
}

/**
 * Image validator which rotates the image.
 */
function _exif_orientation_validate_image_callback(stdClass $file) {
  _exif_orientation_rotate($file);

  // This validator did not produce any errors.
  return array();
}

/**
 * Implements hook_file_presave().
 */
function exif_orientation_file_presave($file) {

  // Provide EXIF Orientation correction.
  _exif_orientation_rotate($file);
}

/**
 * Rotates an image to its EXIF Orientation
 *
 * iPhone 4 and up save all images in landscape, relying on EXIF data to
 * set the orientation properly. This does not always translate well in the
 * browser or other devices.
 * @link: http://www.daveperrett.com/articles/2012/07/28/exif-orientation-handling-is-a-ghetto/
 */
function _exif_orientation_rotate($file) {
  if (function_exists('exif_read_data') && $file->filemime == 'image/jpeg') {
    $file_exif = @exif_read_data(drupal_realpath($file->uri));

    // Ensure that the Orientation key|value exists, otherwise leave.
    if (!is_array($file_exif) || !isset($file_exif['Orientation'])) {
      return;
    }

    // Orientation numbers and corresponding degrees.
    // @note: Odd numbers are flipped images, would need different process.
    switch ($file_exif['Orientation']) {
      case 3:
        $degrees = 180;
        break;
      case 6:
        $degrees = 90;
        break;
      case 8:
        $degrees = 270;
        break;
      default:
        $degrees = 0;
    }
    if ($degrees > 0) {

      // Load the image object for manipulation
      $file_image = image_load(drupal_realpath($file->uri));
      if (image_rotate($file_image, $degrees, 0xffffff)) {
        image_save($file_image);
      }
    }
  }
}

Functions

Name	Description
exif_orientation_file_presave	Implements hook_file_presave().
exif_orientation_form_user_profile_form_alter	Implements hook_form_alter(). Replace the user_validate_picture validator with our own.
_exif_orientation_rotate	Rotates an image to its EXIF Orientation
_exif_orientation_validate_image_callback	Image validator which rotates the image.
_exif_orientation_validate_user_picture	Validates an image uploaded by a user. This is an exact copy of user_validate_picture() except our validator which is added before file_validate_image_resolution(). file_validate_image_resolution resizes the image if it's too large loosing the…